Search results
Results from the WOW.Com Content Network
Density (volumetric mass density or specific mass) is a substance's mass per unit of volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although the Latin letter D can also be used. Mathematically, density is defined as mass divided by volume: [1] where ρ is the density, m is the mass, and V is the volume.
The SI has special names for 22 of these coherent derived units (for example, hertz, the SI unit of measurement of frequency), but the rest merely reflect their derivation: for example, the square metre (m 2), the SI derived unit of area; and the kilogram per cubic metre (kg/m 3 or kg⋅m −3), the SI derived unit of density. The names of SI ...
List of physical quantities. This article consists of tables outlining a number of physical quantities. The first table lists the fundamental quantities used in the International System of Units to define the physical dimension of physical quantities for dimensional analysis. The second table lists the derived physical quantities.
While the values of the physical constants are independent of the system of units in use, each uncertainty as stated reflects our lack of knowledge of the corresponding value as expressed in SI units, and is strongly dependent on how those units are defined. For example, the atomic mass constant is exactly known when expressed using the dalton ...
If the reference is not explicitly stated then it is normally assumed to be water at 4 °C (or, more precisely, 3.98 °C, which is the temperature at which water reaches its maximum density). In SI units, the density of water is (approximately) 1000 kg/m 3 or 1 g/cm 3, which makes relative density calculations particularly convenient: the ...
This new symbol can be raised to a positive or negative power. It can also be combined with other unit symbols to form compound unit symbols. [1]: 143 For example, g/cm 3 is an SI unit of density, where cm 3 is to be interpreted as (cm) 3. Prefixes are added to unit names to produce multiples and submultiples of the original unit. All of these ...
"The candela, symbol cd, is the SI unit of luminous intensity in a given direction. It is defined by taking the fixed numerical value of the luminous efficacy of monochromatic radiation of frequency 540 × 10 12 Hz , K cd , to be 683 when expressed in the unit lm W −1 , which is equal to cd sr W −1 , or cd sr kg −1 m −2 s 3 , where the ...
Symbol Meaning SI unit of measure magnetic vector potential: tesla meter (T⋅m) area: square meter (m 2) amplitude: meter: atomic mass number: unitless acceleration: meter per second squared (m/s 2) magnetic flux density